5)"The World of Rubens", by C.V. Wedgewood and the Editors of Time-Life Books, published be Time-Life books, 1967

6) "The Story of Art", by E. H. Gombrich, published by Phaidon Publishers Inc. 1967

7) History of American Painting Volume Three, "That Wilder Image", The Native School From Thomas Cole to Winslow Homer by James Thomas Flexner, Dover Publications, INC. New York, 1970

8) Theories of Modern Art, A Source Book by Artists and Critics by Herschel B. Chipp, with contributions by Peter Selz and Joshua C. Taylor, University of California Press, Berkeley, Los Angeles and London, 1968

12) Paul Klee, Edited by Carolyn Lanchner, The Museum of Modern Art, New York, Distributed by New York Graphic Society Books/Little, Brown and Company, Boston, Published with the assistance of the J. Paul Getty Trust, 1987